// reference_wrapper example:
#include <functional> // std::reference_wrapper
#include <iostream>   // std::cout

int main() {
  int a(10), b(20), c(30);

  std::cout << "a address: " << &a << " b address: " << &b
            << " c address: " << &c << "\n";
  // an array of "references":
  std::reference_wrapper<int> refs[] = {a, b, c};
  std::cout << "refs:";
  for (int &x : refs)
    std::cout << ' ' << x << " address: " << &x;
  std::cout << '\n';
  return 0;
}
